Furnace bonnet



Oct. 29, 1929. c, J, HOLUB 1,733,986

FURNACE BONNET Filed April 14, 1928 a O a J 9 g 11 'u 4 I g I I 2 2 i t r i a .,.,0,kmml

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the diameter measurements of commercial Patented Oct. 29, 1929 TATE insane.

CHARLES J. HOLUB, OF COLUMBUS, OHIO, A SSIGNOR TO THE W. LAMNECK COMPANY,

OF COLUMBUS, OHIO, A GOBJPORATION OF OHIO I FURNACE BONNET Application filed April 14,

This invention relates to improvements in furnace bonnets and particularly to the means for rendering a furnace bonnet expansible to accommodate for variations in fittings adapting the parts to be conveniently and readily fitted and telescopically joined.

The invention is herein exemplified as incorporated with a furnace casing bonnet of conical form usually fitted over a casing ring. The rings are commercialized under standard sizes either in the form of a sheet metal band, the ends inverted or welded together, or of cast steel as of an integral structure, and under the methods of production are not accurately gauged as to diameter measurements. The fittings, therefore, lack uniformity in diameter measurement for standard sizes, the

variations being more perceptible in the fitlungs of one manufacture over those of anis extensible to meet any variations invmeasurements for corresponding sizes, and as fitted can be securely clamped to the ring, making a very efficient joint. To provide extensibility of the bonnet, two opposing ends;

so of the bonnet wall or body are overlapped and riveted together at one edge to provide a fulcrum with a draw clamp secured to the ends of the metal at the opposite edge of the seam or joint, adapting the collar end of the bonnet to be readily adjusted and clamped to the lit ting to which the bonnet is attached.

To. efliciently seal the joint, a Z or zigzag clip is engaged over each oftheoverlapping ends and between the same, allowing the ends to move in opposing directions for the full degree of adjustment, and extends approximately the full length of the joint for the body portion of the bonnet.

I Further objects and advantages will be more fully set forth in a description of the accompanying drawings, forming a part of this specification, in which:

Figure 1 is a perspective view of a furnace casing bonnet exemplifying the present invention.

1928. Serial No. 270,074.

Figure 2 is a sectional View taken on line cap to required diameter.

Referring to the drawings, 1 indicates a sheet metal furnace casing bonnet of conical form with a concaved top 2- representing a common style of bonnet. The top is perms.- nently seamed tothe conicalbody3, and the body at its lower edge is provided with an annular bead or corrugation 4i and a'milled or fluted collar portion 5 at an angle to the body, which fits over a casing ring 6 in making a casing assembly.

The body being made of sheet metal is lapped seamed, therefore providing a pair of overlapping ends 7,8, longitudinally of the body which are secured together at the upper edge slightly below the seam joining the body with the bonnet by a rivet 9, the ends being loose for the remainder of the joint, adapting the collar and body portion beyond the rivet to be expanded or contracted, hinging on the rivet as a fulcrum. V

The joint at its lower or collar end is provided with a draw clamp 10 for forcibly contracting'the body and clamping the collar por-- tion to the fitting to which the bonnetis tached. The draw clampisof common type, consisting of a pair of angle members each respectivelyriveted to one of the body overlap- ,ping ends and connected by a screw bolt for drawing the angle members together? The overlapping ends 7, 8 are respectively engaged between the folds of a Z or zigzag clip 11 of sheet metal inserted between the ends covering or overlapping the underlying end interior of the bonnet and the overlying end exterior of the cap.

The interposition ofa zigzag chpproduces a slip jointhaving the characteristics of a crimped seam efliciently sealing the connection. In a casing bonnet structure extensibility need only be provided at the collar end and therefore the upper edge of the overlapping ends can be riveted or permanently secured together. A rivet and a crimp seam joining the top to the body yields sufiicient-ly for a limited range of collar adjustment to meet the variations in diameter dimension encountered for a given size of fittings, with the zigzag clip reinforcing the oint, and prevents any buckling of the ends in drawing the collar or lower portion together which would open the seam.

The clip in providing a slip joint can be advantageously employed in various kinds of fittings used in furnace installations and also for straight pipe or conduit sections, and in the latter instance the method as herein dis closed for the bonnet structure by riveting the overlapping ends at one edge may be followed, rendering only one end of the pipe extensible, or, both ends may be provided with draw clamps particularly when the structure is employed as a draw band.

Having described my invention, I claim 1. A furnace bonnet having an annular Wall formed with an expansible seam comprising overlapping edges pivoted at the upper end of the seam, a zigzag sealing clip engaging the overlapping edges and a draw clamp at the lower end of the seam.

2. In a device of the class described, an annular wall formed with an expansible seam comprising overlapping edges pivotally secured together at one end of the seam, a draw clamp at the other end of the seam and a zigzag sealing clip engaging over the overlapping edges.

In testimony whereof, I hereunto subscribe my name.

CHARLES J. HOLUB. 

